Arthur JS, Elce JS, Hegadorn C, Williams K, Greer PA. Disruption of the murine calpain small subunit gene, Capn4: calpain is essential for embryonic development but not for cell growth and division.
Mol Cell Biol 2000;
20:4474-81. [PMID:
10825211 PMCID:
PMC85815 DOI:
10.1128/mcb.20.12.4474-4481.2000]
[Citation(s) in RCA: 265] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/1999] [Accepted: 03/16/2000] [Indexed: 12/13/2022] Open
Abstract
Calpains are a family of Ca(2+)-dependent intracellular cysteine proteases, including the ubiquitously expressed micro- and m-calpains. Both mu- and m-calpains are heterodimers, consisting of a distinct large 80-kDa catalytic subunit, encoded by the genes Capn1 and Capn2, and a common small 28-kDa regulatory subunit (Capn4). The physiological roles and possible functional distinctions of mu- and m-calpains remain unclear, but suggested functions include participation in cell division and migration, integrin-mediated signal transduction, apoptosis, and regulation of cellular control proteins such as cyclin D1 and p53. Homozygous disruption of murine Capn4 eliminated both mu- and m-calpain activities, but this did not affect survival and proliferation of cultured embryonic stem cells or embryonic fibroblasts, or the early stages of organogenesis. However, mutant embryos died at midgestation and displayed defects in the cardiovascular system, hemorrhaging, and accumulation of erythroid progenitors.
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